Krylov subspace methods for block patterned linear systems

This article considers the moment matching using Krylov subspace methods for block patterned linear systems that comprise symmetrically interconnected as well as block circulant systems. Thereby, the block patterned system structure is preserved so that subsequent analysis and synthesis approaches can exploit the special structure of the reduced order system. It is shown that a specific number of moments at arbitrary points can be matched. For the order reduction numerical efficient algorithms can be applied to determine the corresponding Krylov subspaces. The proposed approximation technique is illustrated by means of a simple symmetrically interconnected system.